First off, before I completely yell at you for how ridiculous this thread is, let me just start off by saying that Steam only distributes games. It's a placeholder for companies like THQ or in this case, 2K to market their products. So with that said, you should now know that Steam doesn't determine what the prices are for the games they sell.

Secondly, the third Elder Scrolls, Morrowind, came out in 2002, over 10 years ago and that game is still $20 (or 20 euro). Why? Because the game is fantastic. Just like BioShock is. Now I'm just going to assume that you live with your parents, are still in school, and don't have a job or any means of income if you really think 20 euro is a lot of money to pay for one of the best games ever made.